ABSTRACT

Fibers can be classified as synthetic or man-made (glass, carbon or graphite, aramide, etc.) and natural fibers. There are different types of natural fibers, such as animal or protein fibers (silk, wool, etc.), agro-fibers like bast (jute, flax, hemp, ramie, kenaf, etc.), leaf (sisal, palf, henequen, banana, pineapple, etc.), seed (cotton), fruits (coir, palm) and wood fibers or flour. In fact, synthetic fibers such as nylon, rayon, aramide, glass, polyester and carbon are extensively used for reinforcement of plastics. However, these materials are expensive and are nonrenewable resources. Because of the uncertainties prevailing in the supply and price of petroleum-based products, there is every need to use the naturally occurring alternatives. The interest in natural fiber reinforced polymer composites is growing rapidly because of their high mechanical properties, significant processing advantages, low cost and low density. Natural fibers are renewable resources in many countries of the world; they are cheaper, pose no health hazards and also provide a solution to environmental pollution by finding their new uses vis-a-vis expensive materials and non-renewable resources. Furthermore, natural-fiberreinforced polymer composites form a new class of materials, which seem to have good potential in the future as a substitute for scarce wood and wood-based materials in civil applications. Lignocellulosic fibers like jute, sisal, coir and pineapple have been used as reinforcements in polymer matrices. Natural fibers of vegetable origin include bast, leaf and wood fibers. They may differ considerably in their physical appearance but they have, however, many similarities that identify them as one family. The characteristics of the fibers depend on the individual constituents, the fibrillar structure and the lamella matrix. A fiber is composed of numerous elongated fiber cells. The fiber cells are linked together by means of middle lamellae, which consist of hemicellulose, lignin and pectin. The use of natural fibers including jute faded away with the advent of synthetic polymers that are quite cheap and durable compared to natural polymer materials. This situation is now changing and environmentally conscious citizens are, therefore, reverting to the use of natural polymers wherever possible in place of man-made synthetic polymers to minimize pollution of the environment. Jute has the advantages of being both renewable by agro-efforts and environmentally friendly because of its biodegradability. Nevertheless, attempts have been continually made to improve natural polymers both genetically and chemically. Thus, natural polymers are treated with different materials in different ways to increase their strength, durability and sustainabiHty, while maintaining their inherent degradable character to maintain an environment free of pollution. Jute is mainly used as hessian cloths, ropes, gunny bags, shopping bags, backings of tufted carpets, cheap floor coverings and matting. Jute and traditional jute products are facing stiff competition from synthetic products. For the survival of jute in competition with the synthetic fibers, it must be constantly improved in its physical properties to retain its inherent status.